Bicycle-frame



(No Model.)

A. SIDWELL. BICYCLE FRAME.

Patented Nov. 17, 1896.

UNITED STATES PATENT OFFICE.

AND WALTER MEASURE, OF HIGHLANDVILLE, MASSACHUSETTS.

BlCYCLE-FRAM E.

SPECIFICATION forming part of Letters Patent No. 571,406, dated November17, 1896. Application filed August 13, 1894. Serial No. 520,182. (Nomodel.)

To all whom it may concern:

Be it known that I, ARTHUR SIDWELL, of WValtham, in the county ofMiddlesex, State of Massachusetts, have invented certain new and usefulImprovements in Bicycle-Frames, of which the following is a descriptionsufficiently full, clear, and exact to enable any person skilled in theart or science to which said invention appertains to make and use thesame, reference being had to the accompanying drawings, forming part ofthis specification, in which- Figure 1 is a vertical transverse sectionof the joint of a bicycle-frame; Fig. 2, a transverse section taken online a" 00 in Fig. 1; Fig. 3, a transverse section taken on line y 'y inFig. 1 and looking from the left, and Fig. 4 a plan View showing amodification in the formation of the truss.

Like letters of reference indicate corresponding parts in the differentfigures of the drawings.

My invention relates especially to devices for strengthening theconnections between the tubings from which bicycle-frames areconstructed, whereby tubes of much smaller gage can be employed and thedanger of breaking the tube at the joint-lugs from the vibration can bein a great measure overcome.

In the drawings, A represents the j oint-lug or socket of ordinaryconstruction, which is brazed to the main frame-tube B and in which thetube 0 is secured by pins b and brazing. The tube B within that portioninclosed by the lug is provided with two slots f g, transecting eachother at right angles.

I insert my improved truss D, by which the joint is strengthened, in thetube 0. Said truss consists of two plates h 2', of suitable width to fittightly into said tube 0. These plates are slotted centrally andlongitudinally for about one-half their length and respectively astrideeach other, so that they are'arranged at right angles, as shown in Fig.2. The ends of these plates are projected into the slots f g in the maintube B, as shown in Fig. 3. The whole is then secured together bybrazing when the tube 0 is brazed into the lug. As it is especiallydesirable to lighten the framewithout lessening its strength, this trussadds materially toward producing this effect, because by its use it isnot necessary to extend the lug A entirely around the tube B, but it canbe brazed onto one face thereof, and the truss ends extending into saidtube, as described, will prevent the strain on the tube 0 from breakingaway the lug. The tube 0, moreover, would ordinarily break outside thecoupling-lug. My truss strengthens it at this point and resists thestrain, so that, as specified, much smaller-gaged tubing can be employedin forming the frame. A is, in fact, employed by me more asornamentation or finish to the joint than for its strengtheningqualities and can be entirely omitted, as the truss brazed into theslotsof the main tube and into the frame-tube 0 will secure the partstogether without the use of the lug. In Fig. tthe truss is shown twistedinto a spiral. This construction I employ to obtain greater torsionalstrength, as when used in the hollow crank-shaft of a bicycle. The trussis constructed of similar plates 77.2 i slotted or joined together inthe same manner as before.

Having thus explained my invention, what Iclaim is- The lug Aframe-jointcomprising two tubes the end Witnesses:

K. DURFEE, O. M. SHAW.

